can't iChat vid confer with 4 people


I am trying to get a 4 way video conference going with 2 people in the US and another 1 in the UK. Three of us have .mac addresses and another has aol address.

The conferenceing works fine between any two of us. We all have OS 10.4 or above.

One of our US collegues and myself have the multiple camera icons that indicate that we can host a multiple conference but when we try and do that and invite the other two using the hold down Apple key and select the other three buddies we get a variety of messages telling us we can't do it.

Mine says that my computer can't host a conference but can take part in one. I meet the technocal requirements listed in iChat help and have a 3.5 Gig bradband connection. I'm not sure what the others have but they are certainly G4 or G5 bought very recently so I doubt their specs will be too low.

I desperately need to get this facility set up for a business we're starting together. Can anyone help?